Digital satellite broadcasting and data broadcasting have started, and expectations are running high for these services as new mass media in addition to various broadcasting services. In a field of communication, many access systems such as ISDN, DSL, FTTL and IMT-2000 and the like have been built, IP flat-rate unlimited access service is started, and, broadband communication networks have become available. Thus, it is expected that the Internet becomes widespread more rapidly. The Internet has possibility that it develops as mass media. In the near future, it is expected that digital broadcasting and broadband communication are closely integrated, so that more diversified and interactive services are provided.
The greatest benefit obtained from the interactivity for the viewer is that the viewer can obtain personal information. Terminals for receiving information have become diversified to conform to types and amount of receiving information, purposes, environment, and operability on the information and the like.
Under these circumstances, conventional technologies and the problems will be described from the following three viewpoints.
(1) Since information such as TV and radio information sent from one direction can be obtained without any positive operation, no one feel inconvenience. However, such media have physical limitation for information conveyed by the media. If the viewer is satisfied with the information that is selected and modified by an information provider, there is no problem. When a viewer feels dissatisfaction for lack of information amount, for information providing method such as broadcast time and for broadcasting area and the like, this dissatisfaction can not be solved only by analog media such as conventional analog TV and analog radio. Even if the broadcasting media is digitized for physically increasing information amount, and even if pseudo interactivity is provided to the viewer by using information distribution of a carousel method, the dissatisfaction is not actually solved.
Although a service is started by using the Internet, in which information which can not be conveyed by the broadcasting media is provided, or in which information related to the broadcasting information is provided, since information is provided simply by a plurality of media (multimedia), the problem for providing synchronization and cooperation between items of information provided different media is not solved with the viewpoint of user interface.
Inventions disclosed in Japanese laid-open patent application No.9-160852 and Japanese laid-open patent application No.2000-183835 provide apparatuses for easily obtaining music and video broadcasted by radio and TV. These inventions solve problems on inconvenience for the viewers to obtain broadcast pieces of music and broadcast video after the viewers listened and viewed the pieces of music and images. According to the inventions, additional information (related information) corresponding to the music and the video is sent to the viewer over the media with the music and video, and the additional information is recorded when a request is input to a receiving apparatus when a desired music or image is distributed. Then, the desired music or video is identified via the network by using the recorded additional information, so that the information is obtained.
However, the above-mentioned inventions principally can not fully achieve an object to provide various services for providing related content that is desired by each individual viewer in synchronization with and in cooperation with broadcast content, based on the premise of current various communication access systems and terminals. In addition, the above-mentioned inventions principally can not fully achieve an object that the content provider impartiality provides the services.
That is, according to the conventional technologies, following problems have not been solved. There is no content delivering apparatus that can provide various services. It is not realized to deliver related content in consideration of receiving environment (terminal specification and the like) of the viewer. Status of access systems can not be grasped when delivering.
In addition, according to the conventional technology, the service can be provided only when the viewer inputs a request (record of related information necessary for receiving the service) when a piece of music or an image is delivered. Therefore, reservation or notification of service in synchronization with broadcast content can not be performed. When the viewer wants to obtain the desired service without leaving out any service, it becomes necessary that the viewer incessantly records related information according to the conventional apparatus.
(2) As to digital broadcast such as BS digital broadcast, CS digital broadcast and the like, various items of related information are provided with video and voice, and the items of related information can be referred to while the viewer is watching the video.
However, as for a television receiver which is generally used as a digital broadcast receiving apparatus, when a viewer watches related information, the related information is displayed on a part of a video display part, or the related information is displayed on the whole of the video display part. Therefore, when the related information is displayed, the video image may be reduced, a part of the image may be hidden, or it may be necessary to interrupt watching the video temporarily. When the amount of related information is large, it is difficult to fully grasp the related information simultaneously with viewing the video itself. Thus, it is desirable that the viewer can watch only related information when the viewer wants to do so after the program ends. In addition, since the conventional digital broadcast receiving apparatus displays every received related information, related information that the viewer is not interested in may be displayed.
It is studied to automatically select a broadcast program or related information that the viewer is interested in and to store the selected information by using related information and EPG (Electric Program Guide) information while the viewer does not watch television broadcast. In this case, it is a problem to be solved to obtain information that the viewer is interested in. Conventionally, some methods are proposed, in which the viewer directly inputs a interested keyword to obtain interest information, or interest information is estimated from related information of a program that the viewer watched.
A following document discloses the method for automatically selecting a broadcast program that is a subject of interest of the viewer, (Reference document): Yuichi Yagawa et al. “Study of agent for automatically editing television program corresponding to individual taste” IEICE AI98-55, PP.9-16, December 1998.
In addition, Japanese laid-open patent application No.11-134345 (preference information selection apparatus) discloses a method for estimating interest information from related information of a program that the viewer watched.
However, it is not easy for the viewer to consider and input a keyword indicating information that the viewer is interested in. In addition, the method for estimating related information from interest information of the program has the same problem as the before-mentioned problem that even related information that is not interested in by the viewer is displayed.
(3) As mentioned above, it is possible to multiplex data signals as related information into digital broadcast such as television broadcast or radio broadcast. Therefore, in a digital broadcast receiving apparatus or a terminal connected to the receiving apparatus, processes synchronized with broadcast content can be performed by using the data signal multiplexed in the broadcast. For example, it is possible to deliver related information on a broadcasted television program or a radio program at the same time with the program.
Also in analog television broadcast, it is possible to multiplex data signals in television image signals by a method defined in ARIB STD-B5 “Data Multiplex Broadcasting System For The Conventional Television Using The Vertical Blanking Interval”. Especially, in systems such as one called “Bit Cast” (which can be referred to in Nikkei multimedia, No.28, 1997.10,P.52-P.57), functions are realized such as displaying related information in synchronization with broadcast content by using data signals multiplexed in analog television image signal.
In WWW (World Wide Web), content in a home page is updated in synchronization with broadcast content such as television and radio. The viewer can receive information synchronized with the broadcast content to some extent by accessing the home page.
However, in order to perform processes in synchronization with broadcast content by using data signals multiplexed in broadcast, it is necessary that the terminal obtains data signals multiplexed in the broadcast. That is, there is a problem that the terminal needs to have a function to receive broadcast, or needs to be connected to a broadcast receiving apparatus and have a function to obtain data signals multiplexed in broadcast.
When the terminal does not have such function so that the terminal obtains the data signals multiplexed in the broadcast via a network, there is a problem in that delay time occurs in data signals in the network from a time when an event occurs to a time when an action is executed.
In addition, when providing information related to broadcast video and voice, in a method in which URL is sent with the video and voice, it is necessary that information such as the URL is added to broadcast information. For example, as for broadcast information such as CM that is broadcast repeatedly, it is necessary to add information such as URL corresponding to each item of broadcast information.
Further, in the case where broadcast video and voice are stored and used, there is a problem in that related information can not be obtained at the time when the stored video and voice are reproduced if information such as URL that is broadcast at the same time as the video and voice is not stored.
In the same way, in a method for obtaining related information by using time and CH number as disclosed in Japanese laid-open patent application No.9-160852,when broadcast information that is stored is watched, there is a problem in that related information can not be obtained since the time when the information is watched is different from the time when the information is broadcasted, so that the related information can not be associated with the broadcast information.
In addition, according to the conventional technology, there is a problem in that changing point of image frame of watched broadcast program image can not be grasped accurately.
As mentioned above, according to the conventional technologies, there is a problem in that it is not easy that a viewer obtains information or content that is related to broadcast information or recorded information from a server and the like connected to a network.